The proposed research is aimed at investigating psychological mediators of institutional adaptation of the aged. In contrast to existing research on the social psychological aspects of aging, which is primarily correlational, this proposal describes four experimental field studies that should enable us to derive cause and effect statements relevant to adaptation of the aged. It is hypothesized and preliminary evidence is presented showing that response to a stressful situation such as institutionalization is mediated by the perceived predictability and controllability of the aged person's environment. Study one is designed to assess the effects of increased predictability upon first admission to an institutional environment. The second study examines the effects of giving aged patients control over the delivery of information about their condition. A third study tests the hypothesis that giving subject's feelings of control over their environment will contribute to their physical and psychological well-being. The final study tests the hypothesis that the positive effects of increased control are in part mediated by self-attributions of increased competence. Psychological and physical status indicators will be collected before and after the manipulations are introduced. To the extent that the interventions undertaken in the proposed research prove to be effective, new procedures useful in the treatment of the hospitalized aged will have been indicated. Moreover, psychological mechanisms capable of mediating the psychological and physical status of the aged will have been identified and clarified.